Older adults face many complex demands in their economic and financial decision-making-e.g., critical decisions regarding estate planning, independent living, out-of-pocket medical expenses, and sudden changes in financial roles following the death of a spouse. Moreover, these decisions are frequently made under highly stressful conditions. However, little is known about the influence of stress on decision-making among older adults, and there is a critical need to improve our understanding of this issue. Here, our objective is to characterize the neurobehavioral phenotypes of healthy older persons who are at differing levels of risk for poor decision-making under stress. Our proposal is framed around two specific aims: (1) To investigate the influence of stress on complex decision-making behavior (temporal discounting and decision-making under uncertainty), and the neurobiological correlates of such behavior; and (2) To explore individual difference variables (personality, interoceptive awareness, life stress, executive cognitive functions, prefrontal cortex morphometry, age, and sex) that may influence how stress affects decision-making in older persons. BOLD fMRI and decision-making tasks (decomposable into basic cognitive and economic constructs consisting of validated utility parameters) will be used to investigate decision-making under stress (induced with an fMRI compatible stressor that entails uncontrollability, unpredictability, and social evaluation). We will carry out the aforementioned aims in a population of 200 healthy older persons (ages 60-84 years) comprised of an age- and sex-stratified sample consisting of equal numbers of men and women in each five-year age band, which will allow for an unprecedented examination of how the findings may be age- and sex-related. Our findings will facilitate the detection of older persons at risk for suboptimal decision-making under stress, as well as inform interventions to prevent or treat poor decision-making-e.g., our data will provide foundational knowledge for the development of educational tools to make older persons aware of biases and errors that commonly arise during decision-making under stress, while knowledge of the brain circuits involved could inform targeted pharmacological interventions. The findings could also inform public policy to protect vulnerable elders dealing with life stressors, e.g., from fraudulent advertising, telemarketing schemes, and similar ploys.